Environment Monitoring Unit

Details

  • Mass: 3.5 kg
  • Volume: 3 litres
  • Power: 8 Watts
  • Reliability: 15 year MEO mission
  •  Sensors:
    • SURF: 8 stacked charge collection plates, 7 cm diameter,
    • 8 Proton Telescopes
    • Heavy ion LET sensor
    • RadFETS

The Environment Monitoring Unit (EMU) is a radiation monitor designed and built for use in the Galileo orbit. Its design is based on the Giove-A MERLIN and the Cosmic Radiation Environment and Dosimetry (CREDO) instruments. It is manufactured by Thales-Alenia Space, Switzerland.

EMU consists of four separate sensors:

  • a set of 8 charge collection plates for measuring internal charging currents under shielding;
  • 8 Proton telescopes for measuring energetic proton fluxes;
  • an Linear Energy Transfer (LET) heavy ion sensor;
  • RadFETS for measuring internal doses inside the instrument.

Two instruments have been flown on the Galileo satellites GSAT207 and GSAT215.